The eggs in this story range in diameter from 0.7 to 2 millimeters. The images were made with a scanning electron microscope, which uses beams of electrons to trace the surfaces of objects. The resulting black-and-white images were then colored to reflect the eggs’ natural appearance.

Photographic coverage produced in cooperation with Prüftechnik Uri and School of Applied Sciences, FHNW

Photograph by Martin Oeggerli

Julia heliconian butterfly eggDryas iuliaPerched on the tendril of a Passiflora plant, the egg of the Julia heliconian butterfly may be safe from hungry ants. This species lays its eggs almost exclusively on this plant’s twisted vines.

Photograph by Martin Oeggerli

Stinkbug eggsPentatomidaeStinkbugs often lay their eggs in clumps. Individual eggs are glued not only to each other but also to the leaf on which they are left. The delicate projections may aid, like snorkels, in respiration.

Photograph by Martin Oeggerli

Owl butterfly eggCaligo memnonThe mosaic pattern on an owl butterfly egg looks like a landing pad. At the center is a minute opening, called a micropyle, through which the sperm enters the egg.

Photograph by Martin Oeggerli

Blue morpho butterfly eggMorpho peleidesThe red band signals a chemical reaction that follows fertilization. Inside the egg is the germ of a blue morpho, one of the world’s largest butterflies, with a wingspan of five to eight inches.

Photograph by Martin Oeggerli

Adonis blue butterfly eggLysandra bellargusThe Adonis blue butterfly is rare because it’s choosy. It lays its eggs (like the one above) only on horseshoe vetch, a European perennial. What’s more, it looks for patches cropped by rabbits that allow easy landing.

Photograph by Martin Oeggerli

Red lacewing butterfly eggCethosia biblisOn this butterfly egg, the lacy pattern marks the micropyle, where sperm enters. A similar design appears on the scaly wings that gave the red lacewing butterfly its name.

Photograph by Martin Oeggerli

Dingy skipper eggErynnis tagesThe egg of the dingy skipper is laid on bird’s-foot trefoil. As its name suggests, the grown butterfly, found throughout Europe and in parts of Asia, is not known for its beauty.

Photograph by Martin Oeggerli

Large white butterfly eggPieris brassicaeThe yellow eggs of the large white butterfly are laid in clumps on the undersides of cabbage leaves (above) and brussels sprouts.

Photograph by Martin Oeggerli

Zebra longwing butterfly eggHeliconius charithoniaThe orange hue of this zebra longwing butterfly egg may warn predators: “Eat me if you dare.” The threat would not be idle. The egg contains cyanide and other toxins ingested by adults from the plants they eat.